Name the different type of cell providing cellular barrier responsible for innate immunity in humans?

Neutrophils are the cells that provide cellular barriers in humans. They contain granules that have toxic substances which inhibit the growth of pathogens. These are often the first defence cells that reach the site of infection. These attack pathogens by initiating a process called respiratory burst during which strong oxidising agents such as hydrogen peroxide, hypochlorite and so on are produced.
This is how neutrophils form a barrier against pathogens.   

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